pH of the solution using the Henderson-Hasselbalch equationpH = pKa + log([base]/[acid + base])pKa = 10.33 + log([CO2]/[HCO3-])For NaHCO3, [CO2] = 0.0004 M and [HCO3-] = 0.2025 MFor Na2CO3, [CO2] = 0.0004 M and [HCO3-] = 0.0 pH = 10.33 + log((0.2025)/(0.0004 + 0.2025))pH = 9.25 (Answer)
Percent ionization of 0.120 MM lactic acid(Ka=1.4×10−4): Percent ionization refers to the degree of ionization of a weak electrolyte in solution. It is calculated by taking the ratio of the concentration of ionized species to the initial concentration of the compound multiplied by 100.The formula for percent ionization is:% Ionization = (concentration of H+ ions / initial concentration of lactic acid) × 100Given that, concentration of lactic acid = 0.120 MMInitial concentration of lactic acid = 0.120 MMConcentration of H+ ions = x (as lactic acid is weak electrolyte and it is assumed that x moles of lactic acid ionizes into x moles of H+ and x moles of lactate)Ka of lactic acid = 1.4×10−4Kw/Ka = 1.0×10-14/1.4×10-4 = 7.14×10^-11Now, write the expression for Ka of lactic acid and solve for x Ka = [H+][Lactate]/[Lactic acid]1.4×10^-4 = x² / (0.120 – x)x = 3.87 × 10^-3[Moles of H+]/[Initial moles of lactic acid] x 100 = Percent ionization = 3.87×10^-3/0.120 × 100 = 3.22% (Answer)B) Calculation of percent ionization of 0.120 M lactic acid in a solution containing 8.0×10−3 M M sodium lactate:Given that, concentration of lactic acid = 0.120 MConcentration of sodium lactate = 8.0×10−3 MInitial concentration of lactic acid = 0.120 – 8.0×10−3 = 0.112 MConcentration of H+ ions = x (as lactic acid is weak electrolyte and it is assumed that x moles of lactic acid ionizes into x moles of H+ and x moles of lactate)Ka of lactic acid = 1.4×10−4Kw/Ka = 1.0×10-14/1.4×10-4 = 7.14×10^-11Now, write the expression for Ka of lactic acid and solve for xKa = [H+][Lactate]/[Lactic acid]1.4×10^-4 = x² / (0.112 – x)x = 2.73 × 10^-3[Moles of H+]/[Initial moles of lactic acid] x 100 = Percent ionization = 2.73×10^-3/0.120 × 100 = 2.28% (Answer)C) Calculation of pH of a buffer that is 0.120 MM in NaHCO3 and 0.280 M in Na2CO3:Given that, concentration of NaHCO3 = 0.120 MMConcentration of Na2CO3 = 0.280 MNow, calculate the pKa of the H2CO3/HCO3- buffer system:pKa = pH + log([HCO3-]/[H2CO3])pKa = 10.33 + log(0.280/0.120) = 10.72[HCO3-]/[H2CO3] = antilog (pKa - pH) = antilog (10.72 - 10.33) = 3.65Buffer capacity (ß) = (Change in base/Change in pH) ß = (0.120 × (3.65 + 1))/(1.5 × (10^-5)) = 11680pH = pKa + log([Salt]/[Acid])pH = 10.72 + log(0.280/0.120) = 10.97Answer: 10.97D) Calculation of pH of a solution formed by mixing 65 mL of a solution that is 0.24 M in NaHCO3 with 75 mL of a solution that is 0.17 M in Na2CO3:Step 1: Calculation of moles of NaHCO3 in the first solutionMoles of NaHCO3 = Molarity × Volume (L)Moles of NaHCO3 = 0.24 × (65/1000) = 0.0156Step 2: Calculation of moles of Na2CO3 in the second solutionMoles of Na2CO3 = Molarity × Volume (L)Moles of Na2CO3 = 0.17 × (75/1000) = 0.01275Step 3: Calculation of total moles of HCO3- and CO32-Total moles of HCO3- and CO32- = Moles of NaHCO3 + Moles of Na2CO3Total moles of HCO3- and CO32- = 0.0156 + 0.01275 = 0.02835Step 4: Calculation of new concentration of HCO3- and CO32- after the two solutions are mixedNew concentration of HCO3- and CO32- = Total moles of HCO3- and CO32- / Total volume (L)Total volume = 65/1000 + 75/1000 = 0.14 LNew concentration of HCO3- and CO32- = 0.02835 / 0.14 = 0.2025 MStep 5: Calculation of pH of the solution using the Henderson-Hasselbalch equationpH = pKa + log([base]/[acid + base])pKa = 10.33 + log([CO2]/[HCO3-])For NaHCO3, [CO2] = 0.0004 M and [HCO3-] = 0.2025 MFor Na2CO3, [CO2] = 0.0004 M and [HCO3-] = 0.0 pH = 10.33 + log((0.2025)/(0.0004 + 0.2025))pH = 9.25 (Answer)
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Silver has two stable isotopes. The nucleus, 10747Ag, has atomic mass 106.905095 g/mol with an abundance of 51.83% ; whereas 10947Ag, has atomic mass 108.904754 g/ mol with an abundance of 48.17%. What is the binding energy per nucleon for each isotope?
To calculate the binding energy per nucleon for each isotope of silver, we need to determine the total binding energy of each isotope and divide it by the number of nucleons (protons and neutrons) in each isotope.
The binding energy per nucleon represents the average energy required to remove a nucleon from the nucleus. It is a measure of the stability of the nucleus. To calculate the binding energy per nucleon, we need to determine the total binding energy and the number of nucleons for each isotope. First, we calculate the total binding energy for each isotope using the mass-energy equivalence equation E = mc², where E is the energy, m is the mass, and c is the speed of light.
For the first isotope, 10747Ag, with an atomic mass of 106.905095 g/mol, we multiply the atomic mass by the Avogadro's number to obtain the mass of one mole of atoms. Then we divide the mass by the number of atoms in one mole to get the mass of one atom. The difference between the mass of one atom and the mass of the individual nucleons (protons and neutrons) gives the mass defect. Multiplying the mass defect by c² gives the binding energy of one atom. Finally, dividing the binding energy by the number of nucleons in the isotope gives the binding energy per nucleon.
We repeat the same calculations for the second isotope, 10947Ag, with an atomic mass of 108.904754 g/mol. The resulting values represent the binding energy per nucleon for each isotope of silver.
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Identify the element for this electron configuration: 1s^2 2s^22p^63s^23p^63d^104s^24p.
The element for the given electron configuration 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁰ is Chromium (Cr).
An element's electron configuration is a numeric representation of how the electrons are distributed among the various energy levels and orbitals. It may provide valuable insights into an element's chemical properties and reactions. To comprehend this electron configuration, we'll go through each sublevel from the lowest to the highest energy level: 1s², 2s², 2p⁶, 3s², 3p⁶, 3d¹⁰, 4s², and 4p⁰.
The 1s sublevel contains two electrons (1s²). In the second energy level, the 2s sublevel contains two electrons (2s²), and the 2p sublevel contains six electrons (2p⁶). The 2p sublevel has three orbitals, each of which may accommodate two electrons. As a result, the 2p sublevel contains six electrons. The third energy level contains 3s² and 3p⁶ sub levels. The 3s sublevel contains two electrons, while the 3p sublevel contains six electrons.
Both sublevels' orbitals may accommodate two electrons. The 3d sublevel is also in the third energy level. It contains ten electrons (3d¹⁰). The 3d sublevel has five orbitals, each of which may hold two electrons. As a result, the 3d sublevel has ten electrons. The 4s sublevel is in the fourth energy level. It contains two electrons (4s²). Finally, the 4p sublevel contains zero electrons. As a result, the electronic configuration 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁰ is that of Chromium (Cr).
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Please Help
How many grams of carbon dioxide (CO2) are produced from 85.0 grams of carbon (C)?
Answer: If one mole of carbon monoxide has a mass of 28.01 g and one mole of carbon dioxide has a mass of 44.01 g , it follows that the reaction produces 44.01 g of carbon dioxide for every 28.01 g of carbon monoxide.
Explanation: (May Be Unrelated?)
what hazard is most common from exposure to non-ionizing radiation?
The most common hazard from exposure to non-ionizing radiation is tissue heating.
What are the hazard common to exposure to non-ionizing radiation?The primary risk associated with exposure to non-ionizing radiation lies in the potential for tissue heating. Non-ionizing radiation lacks the necessary energy to dislodge electrons from atoms or molecules, yet it can still transfer energy to matter by inducing molecular vibration.
This vibration, in turn, can elevate the temperature of the exposed tissue, consequently giving rise to a spectrum of health concerns, including:
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Step 1: Consider 0.10 M solutions of acetic acid, ammonia, hydrochloric acid, and sodium hydroxide. Rank these solutions in order of increasing pH (starting from the lowest, and ending with the highest pH value). Please also make a statement, whether each solution is an acidic or a basic one, and provide an explanation why.
Step 2: How many carbon atoms are there in a molecule of each of the following:
a. ethane b. 1-butyne c. propene d. cyclooctane
Please provide molecular formula for each of the four above mentioned compounds.
Example: 2-pentene - contains 5 atoms of C, molecular formula is C5H10
The order of the increasing pH of the solution is Hydrochloric acid, Acetic acid, Ammonia, and Sodium hydroxide.
Molecular formula of compounds: Ethane: C2H6, 1-Butyne: C4H6, Propene: C3H6 and Cyclooctane: C8H16
Rank of solutions in order of increasing pH:
Hydrochloric acid (HCl) is a strong acid that dissociates completely in water. Its pH is very low (less than 1) and it is strongly acidic. It is an acidic solution. It's a 1.0 M solution of hydrochloric acid.
Ammonia (NH3) is a weak base that does not completely dissociate in water. It is a weak base with a pH greater than 7 but less than 10. It is a basic solution. It's a 1.0 M solution of ammonia.
Acetic acid (CH3COOH) is a weak acid that does not completely dissociate in water. It has a pH of around 3.5-4.0, making it a weakly acidic solution. It is an acidic solution. It's a 1.0 M solution of acetic acid.
Sodium hydroxide (NaOH) is a strong base that dissociates completely in water. It has a very high pH (greater than 14), making it a strongly basic solution. It is a basic solution. It's a 1.0 M solution of sodium hydroxide.
So, from the above explanation, the order of the increasing pH of the solution is
Hydrochloric acid, Acetic acid, Ammonia, and Sodium hydroxide.
Step 2: Molecular formula of compounds:
Ethane: C2H6, contains 2 carbon atoms
1-Butyne: C4H6, contains 4 carbon atoms
Propene: C3H6, contains 3 carbon atoms
Cyclooctane: C8H16, contains 8 carbon atoms
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The structural layers of the sun are shown in the cross-sectional diagram. An image of six concentric circles is shown. The six layers thus formed are of varying thickness. The layers in order from inside out are labeled, A, B, C, D, E, F. Which layer represents the radiative zone? A B C D (21 points plus brainliest!)
A layer represents the radiative zone which is at the centre of the cross-sectional diagram.
What is a radio active zone?The layer of a star that lies just outside the core, to which radiant energy is transferred from the core in the form of photons.
In the Sun, the region between the solar core at 0.2 of the Sun's radius and the outer convection zone at 0.71 of the Sun's radius is referred to as the radiation zone, although the core is also a radiative region.
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B
A is inner core B is outer core and there is a few other layers but from what I know looking at this the second layer has always been the radioactive zone.
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Mg(s) + HCl (l) --> H2 (g) +MgCl2 (s) A student conducted an experiment with 2g of magnesium and 3 mL of 6M hydrochloric acid. Equal volumes (3mL) of hydrochloric acid and magnesium strips (2g) were put into each tube. What are the reactants in this reaction?
Answer: Do you have an image so I can solve it?
a 20.-milliliter sample of 0.60 m hcl is diluted with water to a volume of 40. milliliters. what is the new concentration of the solution?
The new concentration of the solution is 0.30 M.
To calculate the new concentration of the solution, we need to consider the dilution process.
Given information:
Initial volume of the HCl solution = 20 mL
Initial concentration of the HCl solution = 0.60 M
Final volume of the diluted solution = 40 mL
The number of moles of HCl in the initial solution can be calculated using the formula:
Moles = Concentration × Volume (in liters)
Initial moles of HCl = 0.60 M × (20 mL / 1000 mL/L) = 0.012 moles
During dilution, the moles of solute remain constant. Therefore, the moles of HCl in the diluted solution will also be 0.012 moles.
The final concentration of the solution can be calculated using the formula:
Final Concentration = Moles / Volume (in liters)
Final concentration = 0.012 moles / (40 mL / 1000 mL/L) = 0.30 M
Therefore, the new concentration of the solution after dilution is 0.30 M.
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why is it necessary to make sure the stopcock is in the open position and then immediately replace the stopper and syringe assembly in the Erlenmeyer flask after adding the hydrochloric acid to the marble chips?
It is important to keep the stopcock open after adding hydrochloric acid to the marble chips in an Erlenmeyer flask for gas collection and accurate measurement of the carbon dioxide produced during the reaction.
Why is it necessary to make sure the stopcock is in the open position and then immediately replace the stopperBy allowing the gas to escape into the syringe or collection apparatus, the experiment can obtain precise gas volume measurements. Additionally, immediately replacing the stopper and syringe assembly helps prevent gas loss and maintains safety by avoiding the build-up of excessive pressure inside the flask.
These measures ensure the reliable and controlled execution of the experiment while obtaining accurate data.
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Which statement about elements is true?
All substances are made up of elements.
There are approximately 50 elements.
An element is made up of different types of atoms.
Most elements are nonmetal.

Answer:
first one is right.
there are 117 elements, so 2nd option is wrong.
elements are made up of one type of atoms, so 3rd is also wrong.
most elements are metal. so 3rd is wrong
Calculate ΔHrxn for
Ca(s) + 1/2 O2(g) + CO2(g) → CaCO3(s)
given the following set of reactions:
Ca(s) + 1/2 O2(g) →CaO(s) ΔH = −635.1 kJ
CaCO3(s) → CaO(s) + CO2(g) ΔH = 178.3 kJ
_____ kJ
The enthalpy change of the reaction is -456.8 kJ.
The balanced chemical equation of the reaction is as follows:
Ca(s) + 1/2O2(g) + CO2(g) → CaCO3(s)
Given reactions:
Ca(s) + 1/2O2(g) → CaO(s) ΔH = -635.1 kJ/mol
CaCO3(s) → CaO(s) + CO2(g) ΔH = 178.3 kJ/mol
The target reaction is a combination of the two given reactions, hence the enthalpy change of the target reaction is the sum of the enthalpies of the two given reactions. It means that:
ΔHrxn = ΔH1 + ΔH2
We have:ΔH1 = -635.1 kJ/mol
ΔH2 = 178.3 kJ/mol
Therefore,ΔHrxn = ΔH1 + ΔH2= (-635.1 kJ/mol) + (178.3 kJ/mol)= -456.8 kJ/mol
Therefore, the enthalpy change of the reaction is -456.8 kJ.
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How many grams are in 2.33 x 1023 molecules of Fe203?
61.9 grams
2.33x10^23 molecules (159.7 g Fe2O3/6.02x10^23 molecules) = 61.9 g
A common characteristic of killers who choose poison as their weapon. This way they can avoid having to confront their victim me directly.
Answer:
The killers who choose poison for killing the victim are the one who does not want to confront the victim. When a knife or a bullet is used to kill a person he may struggle and can cause harm to killer also.
Explanation:
Poison is the most easiest way to kill a person without any struggle. The poison can be given to a person in a juice or through an injection. The poison entered in the body of victim will cause his heart to cease gradually and he will not have energy to struggle with the killer to save his life.
Consider the following balanced reaction: 4Fe + 302 → 2Fe2O3. If 3.2
g of oxygen gas and 3.2 grams of iron are used in this reaction, which
one is the limiting reactant?
O Iron
O Oxygen gas
O Iron III oxide
O None of the above
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A chemist wants to make a gas-liquid solution. However, the gas will not dissolve readily into the liquid solvent. Which step would MOST likely increase the solubility of the gas in the liquid solvent?
A) Expand the volume of the liquid.
B) Increase the temperature of the gas and liquid.
C) Lower the pressure of the gas above the liquid.
D) Increase the pressure of the gas above the liquid.
Answer:
B
Explanation:
Can't really explain it sorry buy heating the solvent tends to increase the solubility
The step that would increase the solubility of the gas in the liquid solvent is to increase the temperature of the gas and liquid.
What is solubility?Solubility is the mixing of any substance into another substance and the fully mixing of the ions of the substance to another substance's ions.
Solubility depends upon temperature, increasing temperature increase the solubility.
In the mixing of gas and liquid, the liquid is solvent and gas is solute, always.
Thus, the correct option is B.
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Identify each of the following half-reactions as either an oxidation half-reaction or a reduction half-reaction.
half-reaction
identification
Br2(1)+2e- →→2Br (aq)
Zn(s) Zn2+(aq) + 2e
The half-reaction Br[tex]_2[/tex](l) + 2[tex]e^-[/tex] → 2[tex]Br^-[/tex](aq) is a reduction half-reaction, while the half-reaction Zn(s) → [tex]Zn^{2+}[/tex](aq) + 2[tex]e^-[/tex] is an oxidation half-reaction.
The given half-reactions are:
Br[tex]_2[/tex](l) + 2[tex]e^-[/tex] → 2[tex]Br^-[/tex](aq)
Zn(s) → [tex]Zn^{2+}[/tex](aq) + 2[tex]e^-[/tex]
The oxidation and reduction reactions are defined as follows:
Oxidation reaction: A half-reaction that includes the loss of electrons is referred to as an oxidation reaction. The oxidation number of the species involved in the reaction is increased in this process.
Reduction reaction: A half-reaction that involves gaining electrons is referred to as a reduction reaction. The oxidation number of the species involved in the reaction is decreased in this process.
Now let us identify which half-reaction is oxidation and which is reduction:
Br[tex]_2[/tex](l) + 2[tex]e^-[/tex] → 2[tex]Br^-[/tex](aq) (reduction reaction)
Zn(s) → [tex]Zn^{2+}[/tex](aq) + 2[tex]e^-[/tex](oxidation reaction)
Thus, the half-reaction Br[tex]_2[/tex](l) + 2[tex]e^-[/tex] → 2[tex]Br^-[/tex](aq) is an example of a reduction half-reaction, while the half-reaction Zn(s) → [tex]Zn^{2+}[/tex](aq) + 2[tex]e^-[/tex] is an example of an oxidation half-reaction.
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If the temperature remains constant and pressure is INCREASED on gas, what will happen to the volume?
The volume will increase.
The volume will decrease.
The volume will not change.
The volume will randomly increase and decrease, and keep doing this.
Answer:
I believe the volume should increase.
From which celestial body is a star born?
A. supernova
B. nebula
C. protostar
D. black dwarf
Answer: B. nebula
Explanation:
Answer:
B. nebula
Explanation:
Birth takes place inside hydrogen-based dust clouds called nebulae.
-TheUnknownScientist
what is motion of a force in kinetic energy
Answer:
Kinetic energy, form of energy that an object or a particle has by reason of its motion. If work, which transfers energy, is done on an object by applying a net force, the object speeds up and thereby gains kinetic energy.
How many molecules are contained in 125 grams of oxygen
gas (O2)?
Answer:
i think its 62.50 :) hope this helped you out
help me........................ please?
Answer:
2 NO2 -> 2 O2 + N2
is a decomposition reaction
Use the drop-down menu to complete the statement. This is why they have similar Atoms of elements in the same group have the same number of chemical properties.
Answer:
valence electrons
Explanation:
i just took the test
30g of Aluminum at 80°c is added to 30g of water at 10°c . Predict
the final temperature of the water
Answer:
the explanation of this 20
Explanation:
20 c
What is the relationship between temperature and volume if pressure is held constant?
A. inverse
B. direct
Answer:
A. inverse
Explanation:
Boyle's Law is a relationship between pressure and volume. In this relationship, pressure and volume have an inverse relationship when temperature is held constant. If there is a decrease in the volume there is less space for molecules to move and therefore they collide more often, increasing the pressure.
How many moles are in 19.82 g Mg?
when was the element copper discovered? Who discovered the element copper?
The Mesopotamians discovered copper (Cu) in 9000 BC.
Just as all the organs in a system work together, the various body
systems work together in a healthy person. Can you think of an
example of two systems and how they work together? Explain
your ideas.
Answer:
the lungs and heart give oxygen to the cells and the sensory system gives messages to the brain
Explanation:
An organism that makes or creates their own food?
A. Consumer
B. Producer
C. Decomposer
I think producer
option is A
Answer:
B. Producer
Explanation:
A producer is normally a type of plant which is food for the animals. Decomposers are things that decompose dead living things into nutrients and etc. Consumers are the ones who normally feed on producers in the food web and are small animals.
Predict whether the entropy change for this process is positive or negative and explain your answer. Then, predict whether the free energy change for the process is positive or negative and explain your answer.
The given question is incomplete. The complete question is:
Consider the spontaneous dissolution of NaCl in water: NaCl(s) → Na+(aq) + Cl −(aq) Predict whether the entropy change for this process is positive or negative and explain your answer. Then, predict whether the free energy change for the process is positive or negative and explain your answer.
Answer: The entropy change is positive. The free energy change for the process is negative and reaction is spontaneous.
Explanation:
Entropy is defined as the degree of randomness of a system. For a system in which randomness increses , the enetropy is said to increase and [tex]\Delta S[/tex] is positive.
As in the given reaction : [tex]NaCl(s)\rightarrow Na^+(aq)+Cl^-(aq)[/tex] , the solid is dissociating to give ions , randomness increases and thus entropy is positive.
Also the dissociation of a molecule requires energy , thus the enthalpy [tex]\Delta H[/tex] is also positive as heat is absorbed by the system.
[tex]\Delta G=\Delta H-T\Delta S[/tex]
[tex]\Delta G=(+ve)-T(+ve)[/tex]
[tex]\Delta G=-ve[/tex] when Temperature is high.
Consider the spontaneous dissolution of NaCl in water: NaCl(s) → Na+(aq) + Cl −(aq)
Predict whether the entropy change for this process is positive or negative and explain your answer. Then, predict whether the free energy change for the process is positive or negative and explain your answer.
The given question is incomplete. The complete question is:
Consider the spontaneous dissolution of NaCl in water: NaCl(s) → Na(aq) Cl −(aq) Predict whether the entropy change for this process is positive or negative and explain your answer. Then, predict whether the free energy change for the process is positive or negative and explain your answer.
Answer: The entropy change is positive. The free energy change for the process is negative and reaction is spontaneous.
Explanation:
Entropy is defined as the degree of randomness of a system. For a system in which randomness increses , the enetropy is said to increase and is positive.
As in the given reaction : , the solid is dissociating to give ions , randomness increases and thus entropy is positive.
Also the dissociation of a molecule requires energy , thus the enthalpy is also positive as heat is absorbed by the system.
when Temperature is high.
Which of these ideas did you include in your answer?
✔️ When a crystalline solid dissolves, it becomes more disordered.✔️ When disorder increases, ΔG is positive.✔️ This process probably has a positive ΔS .✔️ The process is spontaneous.✔️ Spontaneous processes have ΔG < 0; the process has a negative ΔG .
Have a Nice Day .
C-14 is an isotope of the element carbon. How does it differ from the carbon atom seen here?
A) C-14 has two more protons.
B) C-14 has two more neutrons.
C) C-14 has a larger atomic radius.
D) C-14 has two additional valence electrons.
This column of the periodic table represents the halogen family. This is a family of reactive elements. How do the members of the family differ? How are they alike?
A) The mass numbers differ; they have the same number of protons and valence electrons.
B) They have different atomic numbers and mass numbers; they have the same number of electrons.
C) They have different atomic numbers and mass numbers; they have the same number of valence electrons.
D) They have different numbers of protons, neutrons, and valence electrons; they are all gases at room temperature.
Young stars, just beginning their life in the galaxy, would contain mostly
A) carbon.
B) helium.
C) iron and nickel.
D) hydrogen and helium
C-14 is an isotope of the element carbon and it differs from the carbon atom in the fact that it has two more neutrons. The correct option is B) C-14 has two more neutrons.An isotope is referred to as the element of the same atomic number, and isotopes possess a different number of neutrons in their nucleus.
The correct option is B
For example, the carbon-14 isotope of carbon has 6 protons and 8 neutrons, whereas the carbon-12 isotope of carbon has 6 protons and 6 neutrons .This column of the periodic table represents the halogen family. This is a family of reactive elements. Members of the halogen family differ in that they have different atomic numbers and mass numbers; they have the same number of valence electrons. Hence, the correct option is C) They have different atomic numbers and mass numbers; they have the same number of valence electrons.
The halogens are a family of highly reactive non-metallic elements from Group 17 (the seventh column) of the periodic table. The halogens are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).Young stars, just beginning their life in the galaxy, would contain mostly hydrogen and helium. Hence, the correct option is D) hydrogen and helium. During the star formation process, these two gases are pulled together by gravity to create nuclear fusion reactions. As a result of this reaction, the hydrogen is converted into helium.
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